Pain Patches and other pain medicin for dogs cats and humans

[malernee]

Post operative pain at the human hospital is delivered with a IV pain
button.*animal* has a pain patch on that will deliver similar pain
medication. The patch will last up to five days. If *animal* is showing
no pain in 3 days we can remove the patch to prevent skin rash from the
tape adhesive. The patch should be removed and flushed down the toilet to
prevent animals and small children from eating it.

<< Minimizing Postoperative Discomfort in Dogs and Cats
Vet Med 94[3]:259-265 Mar'99 Symposium 28 Refs

Peter W. Hellyer, DVM, MS, Dipl. ACVA
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins. CO 30523

- Pain, anxiety, disorientation, and residual anesthetic drug effects may all affect animals postoperatively. It is safe to assume that virtually all animals experience discomfort after the tissue trauma of surgery. To ensure these patients' comfort, continual observation and appropriate treatment are often critical, particularly within the first 12 to 24 hours. But even experienced veterinarians and their staffs frequently have difficulty determining whether the postoperative behaviors they observe are indicative of pain, anxiety, or some other factor.
Rather than wait for an animal to exhibit a behavior suggesting discomfort, consider preemptively treating the patient for anxiety or pain. This approach prevents an animal from having to prove that it is anxious or in pain and is especially important in animals incapable of demonstrating behaviors indicative of discomfort. Moreover, preemptive therapy is beneficial because it may prevent you from having to decide which behaviors warrant administering analgesia or sedation. A set of prescribed behaviors that may prompt one veterinarian or staff member to administer analgesic or sedative drugs may differ from that of another caregiver. It has been argued that providing patient comfort should be the primary objective of veterinary (and human) health-care providers. A proactive approach to preventing pain after surgery and aggressively treating pain when it is recognized will greatly improve the comfort of our veterinary patients. This article describes the steps to take before, during, and after surgery to recognize and minimize patient discomfort.

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SUMMARY:

Postoperative patients may experience pain, anxiety, disorientation, and residual anesthetic drug effects. This article gives pointers on assessing both the procedure and the patient’s pre-, intra-, and postoperative condition with respect to minimizing the patient’s discomfort. Achieving this goal is best done in the first 12 – 24 hours after surgery.

Step 1: Assess the patient’s health and behavior

Obtain a complete history.
Perform a complete physical examination
Perform appropriate diagnostic tests
Note the amount of anxiety/energy. (It may indicate pain). Administering anxiolytics (acepromazine maleate) may help smooth the recovery. (These are not analgesics, but they may augment the effect of analgesics.)
Step 2: Consider the nature of the procedure

Evaluate the procedure and its pain potential (i.e. onychectomy or cranial cruciate ligament repair versus suturing a minor laceration versus endoscopy or radiography). See chart below.
Give analgesics to any patient undergoing any invasive procedures that will result in tissue trauma.
Pain Levels Associated with Common Surgical Procedures
Procedure Pain Level Protocol Requirements
Minor: physical exam, restraint, radiography, suture removal, cast application, bandage change, grooming, nail trim No pain Moderate to heavy sedation (only if needed); no analgesic required
Minor surgeries: Suturing, debridement, urinary catheterization, dental cleaning, ear exam & cleaning, abscess lancing, removing cutaneous foreign bodies Minor pain Heavy sedation with analgesia or short anesthesia, with/without local anesthesia
Opioid agonist-antagonist recommended with a 2-agonists or phenothiazine tranquilizers

Moderate surgeries: ovariohysterectomy, castration, cesarean section, feline onychectomy, cystotomy, anal sacculectomy, dental extraction, cutaneous mass removal, severe laceration repair Moderate pain Analgesic premedication AND general anesthesia AND postoperative pain management (a 2-agonist with opioid agonist-antagonist, or full opioid agonist without/without NSAIDs)
Major surgeries: fracture repair, cruciate ligament repair, thoracotomy, laminectomy, exploratory laparotomy, limb amputation, ear canal ablation Severe pain Analgesic premedication AND general anesthesia AND postoperative pain management (full opioid agonists with/without NSAIDs)

Step 3: Manage the pain before it begins

Preemptive analgesia: administration of analgesics prior to a procedure to inhibit or block the transduction of nociceptive impulses along the pain pathways

Prevents sensitization of pain pathways that result in heightened pain levels (hyperalgesia)
Neuronal changes seen in hyperalgesia may be responsible for opioid tolerance
Improves patient comfort and reduces the need for postoperative analgesics
Analgesics may affect the cardiopulmonary system
Analgesics may increase recovery time (increased observation needed)
Combining some of the analgesics below increases the chance of preventing and treating pain:

Opioids: morphine, oxymorphone hydrochloride, fentanyl citrate, butorphanol tartrate
Alpha 2-agonists: xylazine hydrochloride, medetomidine hydrochloride, detomidine hydrochloride
Nonsteroidal anti-inflammatory drugs (NSAIDs): ketoprofen, carprofen, etodolac, meclofenamic acid
Local anesthetics: lidocaine, bupivacaine hydrochloride
Ketamine: ketamine hydrochloride (recent studies suggest this may prevent sensitization)
Example of an analgesic protocol for routine ovariohysterectomy or castration in a healthy dog
Premedication Anesthetic induction & maintenance Postoperative analgesia
Morphine* (0.5 – 1 mg/kg SC)
With/without acepromazine (0.01 – 0.03 mg/kg SC)

With/without atropine (0.02 – 0.04 mg/kg SC)

*oxymorphone (0.05 - 0.1 mg/kg), butorphanol, buprenorphine, or nalbuphine may be substituted for morphine
Tailor to the animal Morphine (0.5 mg/kg SC or IV), additional doses PRN or q4h
Ketoprofen [extralabel] (2 mg/kg SC), do not administer if receiving carprofen, is hypovolemic, was hypotensive under anesthesia, or has renal disease

Example of an analgesic protocol for routine ovariohysterectomy or castration in a healthy cat
Premedication Anesthetic induction & maintenance Postoperative analgesia
Morphine* (0.25 mg/kg SC)
Atropine (0.02 – 0.04 mg/kg SC)

Medetomidine [extralabel] (0.01 – 0.02 mg/kg IM) given 10 minutes after morphine & atropine

*oxymorphone (0.025 mg/kg), butorphanol, buprenorphine, or nalbuphine may be substituted for morphine
Tailor to the animal Morphine (0.25 – 0.5 mg/kg SC or IV), additional doses PRN or q4h
Ketoprofen [extralabel] (2 mg/kg SC) do not administer if hypovolemic, was hypotensive under anesthesia, or has renal disease. Can redose at 1 mg/kg q24h for 2 – 3 days.

Example of an analgesic protocol for onychectomy in a healthy cat
Premedication Anesthetic induction & maintenance Local anesthetic ring block Postoperative analgesia
Morphine* (0.25 – 0.5 mg/kg SC
Atropine (0.02 – 0.04 mg/kg SC)

Medetomidine [extralabel] (0.01 – 0.02 mg/kg IM) given 10 minutes after morphine & atropine

*oxymorphone (0.025 – 0.05 mg/kg), butorphanol, buprenorphine, or nalbuphine may be substituted for morphine
Tailor to the animal; ketamine induction may help prevent hyperalgesia Lidocaine
(2 mg/kg) plus bupivacaine (2 mg/kg) mixed in the same syringe (see details below)
Morphine (0.25 – 0.5 mg/kg SC or IV), additional doses PRN or q4h
Ketoprofen [extralabel] (2 mg/kg SC) do not administer if hypovolemic, was hypotensive under anesthesia, or has renal disease.

RING BLOCKS: (Authors suggestions) Do not clip the feet. Disinfect with a surgical scrub/alcohol technique. Mix lidocaine (2 mg/kg) and bupivacaine (2 mg/kg) in the same syringe, and divide into the number of paws to declaw. With a 25-ga needle, infiltrate mixture SC at the carpal or tarsal level just prior to starting the procedure. Use 4 – 6 injections dorsally (from medial to lateral just proximal to the carpus or tarsus), then use a small amount on the palmar surface (between the carpal & metacarpal or tarsal & metatarsal pads). Analgesia lasts about 6 hours. Lidocaine has a quick onset/short duration of action; bupivicaine has a slow onset/long duration of action.

Example of analgesic protocol for a cranial cruciate repair in a healthy dog
Premedication Morphine (0.5 – 1 mg/kg SC) or oxymorphone (0.05 – 0.1 mg/kg SC)
With/without acepromazine (0.01 – 0.03 mg/kg SC)

With/without atropine (0.02 – 0.04 mg/kg SC)

Anesthetic induction & maintenance Tailor to the animal
Epidural (before surgery)
*periodically check patient for distended bladder and urine retention during postop.
Preservative-free morphine (Astramorph/PFÔ ) (0.1 mg/kg) plus bupivacaine (0.5 mg/kg) into the epidural space at L7 – S1. If injection is subarachnoid (CSF present), use same dose of morphine but decrease bupivacaine to 0.2 mg/kg. Position dog surgery side down for 5 – 10 minutes after epidural
With/without intra-articular analgesia Bupivacaine (up to 3 mg/kg) with/without preservative-free morphine (0.1 mg/kg) injected into the joint after the joint capsule is closed.
Postoperative analgesia Morphine (0.5 mg/kg SC or IV); additional doses PRN or q4h.
Ketoprofen [extralabel] (2 mg/kg SC); do not administer if the patient is receiving carprofen, is hypovolemic, was hypotensive under anesthesia, or has a history of renal disease.

Step 4: Consider presurgical local and regional techniques

Local anesthesia blocks pain by blocking the transduction of nociceptive impulses
Local anesthesia minimizes cardiopulmonary depression by decreasing the total dose of anesthesia required for the procedure
Local anesthesia usually improves recovery
See the chart above for the use of carpal or tarsal ring blocks in cat onychectomy
Step 5: Recognize and treat postoperative discomfort

Pain behavior may be influenced by the patient’s species, breed, age, health status, environment (home vs. veterinary clinic), and the procedure being performed.

Postoperatively look for:

Return to normal behavior
Obvious signs of relaxation (i.e. sleeping)
Reduction of atypical behavior signs
Consider using supplemental postoperative analgesia after extubation, if patient is regaining consciousness and its cardiopulmonary parameters are stable.

Opioid analgesics cause minimal cardiopulmonary depression in most dogs & cats, but will cause sedation, so body temperature must be monitored (to avoid hypothermia).
If patient is anxious or panicked during recovery, administer pain medications first, then give a sedative or tranquilizer (acepromazine, diazepam) PRN.

Ketoprofen decreases the amount of postoperative opioids needed, but does not eliminate the need for supplemental analgesia.
NSAIDs should be given only to patients that are well-hydrated, and that do not have renal, hepatic, or gastrointestinal disease.
Partial list of behaviors that suggest pain or anxiety in dogs and cats after surgery
Changes in personality or attitude Sudden aggressiveness in a docile animal or vice versa. Attempts to bite, especially if a painful area is palpated.
Activity level Restlessness, pacing, repeatedly getting up and down. Recumbent or reluctant to move/guarding of a painful area. Abnormal activity may not be noticed on brief observations.
Inability to sleep Won’t lie down even if exhausted. Sits propped up in the corner of the cage.
Facial expression Dull eyes, dilated pupils, staring into space, pinning of ears or grimacing, sleepy, photophobic appearance
Abnormal vocalization Vocalization, especially if painful area is palpated or moved. This is an unreliable trait.
Licking, biting, scratching, or shaking Suspect discomfort, especially if directed at the painful area. Can lead to self-mutilation.
Posture and ambulation May limp or carry a painful appendage. May tense the abdomen/back muscles (tucked up).
Physiologic parameters Increased heart rate, blood pressure, respiration, and body temperature
Changes in the hair coat Ruffled or greasy fur indicate lack of grooming or piloerection
Appetite and thirst Decreased food/water intake. (Weight loss & dehydration are usually long term indicators).

Step 6: Continue the analgesic therapy

Postoperative pain peaks in the first 24 hours after the procedure
Analgesic therapy should be given on a fixed schedule during the first 24 hours, then tapered
Dispense oral analgesics for the following 2 - 3 days, if patient sent home with owner >>
**
Transdermal fentanyl patches in small animals.
J Am Anim Hosp Assoc 40[6]:468-78 2004 Nov-Dec

Hofmeister EH, Egger CM
Fentanyl citrate is a potent opioid that can be delivered by the transdermal route in cats and dogs. Publications regarding transdermal fentanyl patches were obtained and systematically reviewed. Seven studies in cats and seven studies in dogs met the criteria for inclusion in this review. Dogs achieved effective plasma concentrations approximately 24 hours after patch application. Cats achieved effective plasma concentrations 7 hours after patch application. In dogs, transdermal fentanyl produced analgesia for up to 72 hours, except for the immediate 0- to 6-hour postoperative period. In cats, transdermal fentanyl produced analgesia equivalent to intermittent butorphanol administration for up to 72 hours following patch application.
***
U.S. Warns of Dangers From Patch Used for Pain



New York Times
By DENISE GRADY
Published: July 16, 2005
The government warned yesterday that painkilling skin patches could cause drug overdoses and said it was investigating reports of serious side effects and 120 deaths that might have resulted.

Forum: Health in the News
The patches, containing the narcotic fentanyl, are marketed under the name Duragesic by Janssen, a company owned by Johnson & Johnson. A generic version was put on the market in February by Mylan Laboratories. Duragesic had sales of more than $2 billion in 2004.

The patches are intended for people with moderate to severe chronic pain that requires treatment around the clock for an extended period of time and that cannot be controlled by other narcotics alone, the F.D.A. and the manufacturer say. Only those already tolerant of narcotics, as some cancer patients are, should use the patches. People recovering from surgery, or suffering from short-term pain for other reasons, should not.

A spokeswoman for the Food and Drug Administration said the 120 deaths had occurred since Duragesic was first approved in 1990 and added that the investigation was still going on and that it was not known whether the product actually caused the deaths and other problems reported in users.

Describing fentanyl as a "very strong narcotic," the F.D.A. issued a public health advisory stating that some patients and doctors might not be fully aware of its dangers. An overdose can cause a person to stop breathing; taking off the patch will not reverse the effects because the drug has already built up in the person's system and may continue to be absorbed from the skin for 17 hours or more.

The advisory warns that the patches must be used exactly as prescribed and that doctors and patients must be alert for signs of overdose like breathing difficulties, extreme tiredness and feelings of faintness or dizziness.

The advisory notes that people wearing the patches may suffer overdoses or other serious side effects if they drink alcohol, have an increase in body temperature or are exposed to heat from sources like heating pads, electric blankets, heat lamps, saunas, hot tubs or heated water beds. Certain medicines, including antifungals and some drugs used to treat H.I.V., can also lead to fentanyl overdoses in people wearing the patches.

In June, Janssen sent a warning letter to doctors stating that deaths and other serious medical problems had occurred in people who were accidentally exposed to Duragesic by sitting on a patch or touching it while putting it on someone else. In addition, a patch accidentally stuck to a child who was hugged by an adult who had been wearing it; the company did not say whether the child survived.

Fentanyl in any form is also popular with drug abusers, and a report issued this month by the National Center on Addiction and Substance Abuse said the patches were "increasingly implicated in cases of abuse," and were often stolen from hospitals and clinics and then cut open to extract the fentanyl.

A spokesman for Johnson & Johnson said the patches, when used properly, were an important treatment. Mylan declined to comment on the public health advisory.